It's a communication protocol Pete - essentially born out of European Information Bus, Batibus and an early form of a european home automation system.

It's OK - there are alternatives, it does some thing well and not others - useful for dragging say lighting control and room ventilation, cooling in cellular offices into some sort of management - fast enough for lighting control, but expensive.

I've done a few hotels with it and a very large site where luminaires were on DALI and the control was KNX (faster than DALI)

In my experience however, a lot of the big commercial controls guys won't use it - so it's limited in that sense, although it's an option on many big manufacturers kit. If you go to the market, you are more likely to get a Trend system or Seimens Desigo offered than true KNX for sure - people don't really bother to worry about open and closed BMS protocol too much (at the moment at least) - the integration really needs to take place at the level that KNX is usually used.

Shrek I never thought I would ever ever in my life address a communication to Shrek but here it is...

KNX is an open protocol system which means that it is able to communicate with quite a few of the existing systems, such as Dali.

I attended a one day course a few months back. The course I went on was specific to KNX in association with Schneider kit. It is indeed very impressive and I have it in mind quite often since then. I like it very much.

Now, as OMS says, the KNX system is faster than Dali and some of the others, which can be good but let me make up an example for you; You have a large public space, let's say a museum, in which the public are looking at the displays of old Dinosaur bones and they need bright light. At about 6pm the museum becomes a moody bar (nice, I already like it there) and at 11pm it becomes a throbbing metropolis salsa dancing joint. The people in there may stay or may drift off as the environment changes. What you need in there is a gradual change in lighting level, temperature, breeze and so on. So a Dali type system would be perfect. What you don't want is a sudden change in the ambiance so a KNX could be a poor choice.

KNX installations FYI: Teminal 5 and The British Library.
Lights on or Lights off. Simple.

I decided against the full paid course, for now, for two reasons;

1) This is harsh but true. I met the presenter of the KNX courses on that day and he mumbles. Sorry folks but if you are going to present a course to me I want to be able to concentrate on the learning and not on trying to work out what you are saying.

2) I think these automation companies are inventing licenses in order to try and trap us into loyalty. I'm sorry if this sounds harsh too, but if you want me to go out there and sell your product for you then make it attractive to me to do so and appropriate for my client. You need to think about paying me to come on your course because what you are after is my hard-earned reputation and my client base. Don't charge me the earth in the hope that I will fall at your feet and be loyal to you. The most suitable product for my client will get my recommendation. I'm an electrician, not an agent.

So Shrek, I'd say look at lots of the options before spending £1,000+ on a course with a certificate. You can go on a Lutron course for free and get a certificate and it's not a bad day's education either. If you have not been on one then go. If KNX is likely to be your thing I know of at least two accredited installers so why not just specify it and get them in to quote for you? Then you can put your feet up, watch loose women and drink tea while somebody else gets it up and running for you.

All that said, I am not overlooking any of it and I want to know more. I will continue to go on short courses but my limit is £100 a day. I am absolutely not prepared to shell out loads of money when I genuinely think the opposite should apply. They want HSBC? I 've got them, they can come and buy them from me, They want the Local Education Authority? I've got them and they can come and buy them from me.... and so on. They didn't come to me just by spending a grand and you lot really know how true that is.

I suppose that in my heart my morals are with my customers and I want them to have what is right for them.

I agree with much of what Zs has said about KNX - it's appropriate for some applications - but essentially, it's a room or small system information protocol - it simply doesn't cut the mustard when you really do have big systems that need both down in the weeds integration, and a far higher level management function. (don't ever try and get a full AC office suite to step change because of a function on KNX - and god forbid you have a change of tenant and you need thier Cat A/B fit out to start talking to landlords kit.) - to do all that you need what usually turs out to be several protocols, all doing the bit they are good at - I mentioned Desigo as an example - take a look at the levels of control and what protocol they use at various levels

As for charging you good money to sell thier product, then for sure, you work hard developing that customer base for them - and then you get rinsed for doing it - no way Jose.

As a specifier, we have a different role - essentially that of not locking clients into closed protocols, or specifiying the wrong system for thier needs - it's true to say that the vast majority of clients don't need complex controls - they can't manage them and it costs a fortune.

You need to specify the right product for that application - in some respects, KNX is a product looking for a home - it's great to know that you could turn your office lights on from 3000 miles away - but really, do you need to ?.

Always worth remembering, when it comes to any form of control system that whilst we as building designers like to think we know what users want - we aren't the users, and more times than not, our carefully planned control systems are found to be seriously wanting - the frustration of not getting feedback when you just want to turn a light on or off, or add a bit more cooling in the meeting room (or more usually a lot less cooling in a meeting room) is almost palpable if you spend any time actually talking to users.

KNX - it's good, but not that good - and there are many more competing protocols with good and bad features - pick the one you lock into with care - it's a fickle market place.

All that said, I am not overlooking any of it and I want to know more. I will continue to go on short courses but my limit is £100 a day.

Buy a book on controls in the first instance - as in a basic introduction to feedback loops, digital on-off and analogue proportional integral and derivative control.

Then get to grips with specifying the control strategy and developing the relevant inputs and outputs of a system.

(ie the system shall operate under timed control with photocell inhibit to avoid operation outside predetermied external illuminace level - provide time control with command authority to allow part night or curfew settings. Provide input from security and fire alarm systems to ensure external lighting operates when either or both systems activates. Provide hand auto off control to ensure lighting may be forced on or forced to off (blackout) from XXX number defined locations)

From there you'll see inputs - time, lux, fire, security, hand - and output to luminaires - do you need feedback ?

Then start with the HVAC, general lighting, emergency lighting etc etc etc strategies - as an example, do you need very fast or very slow control to modulate the temperature of supply air into an operating theatre - is airside control faster than room control - if I change the tempeature set point, will I have air coming in that's still too hot or cold - would it be faster with water side control of the heating or cooling coil - do i modulate that conrol valve as on-off, is a simple proportional respose appropriate (is overshoot a problem ?) or do I need to find the integral of the set point and the delivered condition and change the rate of response of the valve - ie determine the derivative to set the valve position to get closer to my design condition without the overshoot or undershoot. Do i have a positiuve pressure regime to maintain whilst I'm doing all this fiddling about - If you get it wrong, and KNX can't respond then you'll put the system into oscillation and that's a theatre out of condition, a proabale infection control issue and an operation cancelled

That's what forms the basis of control engineering - from there could you build the system - then you can worry about what protocol to use, tested by the requirements.

I agree, the best way to learn is to play. Maybe grab a cheap course after playing with some kit for a while just to learn a few tips and tricks but you're never going to learn in a £1000 per day (1 day) course what you'll find out yourself with a bit of playing.

Slightly off topic but we've been playing with a bit of quite nice looking door entry kit that runs over an IP network. For an application we have we need to replace the cat5 cable that the book specifies with a microwave link.... Three hours playing yesterday to get the microwave to be completely transparent to the door entry kit and happy days. No course will teach you that as we've got three different suppliers kit in the network but it does exactly what the customer ordered.

It's good to train, but equally it's good to give yourself maybe half a day a month to "play"

On my little site all the residential units have a KNX Schneider mini BMS system control open protocol, it controls the HVAC, lighting, access, CCTV, and Fire alarm monitoring
Basically a fancy intelligent switch mini BMS system with graphics

After getting a couple of hitches on the first couple the guys on site are now experts on them.
So as others have said its probable better to have a play around with a couple if you have access to and then if you feel you need to attend their course but a bag of sand a course seems a little expensive
Schneider or whoever would not sell you one without trouble shooting technical backup and step by step guidance.

A few years back I did a one day KNX intro course at Ivory Egg / knx shop. A good insight into the technology and its application and will give you a better idea if its suited to your requirements rather than splashing out £1000+ to find out its not for you!

Why do these companies exist? They charge a fortune to train, charge for membership and licences and off you a fancy on off switch for lighting, there are loads of far far better solutions that do far more for much less money!

thanks for all the reply's , so what would be the best route to learn regarding smart homes and lighting. it seems a minefield , I understood that KNX was the general standard for dali and other systems but I seem to have got that wrong. its definitely something I would like to get into so if anyone knows the best route to take your advice would be greatly appreciated